Cancer patients undergoing radiation therapy and IUDR treatment have shown signs of Mucocytosis. It is believed that Thymidine, an endogenous nucleoside could suppress this action by a competitive mechanism. Thymidine as such has a very short half-life of 3-4 minutes. With continuous I.V. infusion, however, the half-life is increased to 10.8 days due to saturation of biochemical pathway. For this reason, as well as the fact that Mucocytosis is a local ailment, a mouth-wash was chosen as the dosage form of choice. A vehicle has been developed for this purpose in which drug solubility was found to be about 4.5%. For comparison purposes, a commercial mouth-wash (Cepacol) was also considered. Stability studied of the drug in these vehicles as well as in water at 45 degrees C is in progress. Clinical trials would be undertaken as soon as stability study is completed.